220 
PACIFIC SCIENCE, Vol. V, July, 1951 
a broad obovate median longitudin- 
al white band that tapers to pos- 
terior margin) 
.... {Stegomyia) mediopunctatus perplexus 
Hind tarsal segments I-V with white 
markings 63 
63. Tibiae ringed with white just before 
the middle; hind tarsal segments 
IV-V all white, may be a few apical ^ 
black scales on IV ; (scutum marked 
with a pair of narrow subdorsal 
white lines from anterior margin 
halfway to level of wing bases, a 
large white patch laterally before 
wing base, and 3 short longitudinal 
pale lines between the wing bases) 
{Stegomyia) desmotes 
Tibiae not ringed near the middle; 
hind tarsal IV with a distinct apical 
dark band 64 
64. Hind tarsal segment V with at least 
some dark scaling apically, occa- 
sionally all dark; the scales along the 
posterior portion of the scutum all 
broad; scutum with a pair of broad 
subdorsal white bands anteriorly 
and a large white patch before the 
wing base {Stegomyia) gardnerii 
Hind tarsal segment V all white; the 
scales along the posterior margin of 
the scutum narrow or mostly so; 
scutum not marked as above 65 
65. Scutum with a pair of thin longitudi- 
nal submedian lines and a paired 
broadened antero-lateral crescent- 
shaped marking (composed of 
broad silvery scales) ; female clypeus 
with white scaling . . {Stegomyia) aegypti 
Scutum with a narrow tapered median 
longitudinal band; female clypeus 
not scaled 66 
66. Dorsal abdominal bands basal, de- 
tached from the lateral spots ; pleur- 
al scale patches not forming 2 
sharply differentiated longitudinal 
white bands ...... {Stegomyia) alhopictus 
Dorsal abdominal bands subbasal on 
more posterior segments, attached 
on at least some segments to the 
lateral spots; pleural scale patches 
arranged into 2 sharply differen- 
tiated longitudinal white bands ... 67 
67. Mid femur anteriorly with a median 
longitudinal white line, may be 
poorly developed in female (rarely 
absent) ; scutum with a line of white 
scales on antero-lateral margin .... 
{Stegomyia) paullusi 
Mid femur without anterior median 
longitudinal pale markings; scutum 
without a line of white scales on 
antero-lateral margin 
{Stegomyia) scutellaris 
Fourth Instar Larval Key 
1. Anal plate with an acus (otherwise 
bare except possibly for spicules on 
posterior margin) 2 
Anal plate without an acus 7 
2. Comb of 8-10 teeth in a row 
{Aedimorphus) vexans nocturnus 
Comb of 16 or more scales in a patch . 3 
3. Antenna slender, very few fine spic- 
ules scattered near base; comb of 
40-80 scales 4 
Antenna rather stout, large spicules 
scattered over most of length; 
comb of 16-28 scales 5 
4. Head hair 4 with 13-16 branches; 
ventral brush with 10 tufts 
[Finlaya) leucopleurus (in part) 
{Finlaya) aureostriatus (in part) 
Head hair 4 with 4-8 branches; ven- 
tral brush with 12 tufts 48 
5. Antennal hair with 1-4 branches; 
ventral brush with 15-17 tufts .... 
{Ochlerotatus) vigilax ludlowi 
Antennal hair with 5-13 branches; 
ventral brush with 12 tufts 6 
6. Head hair 5 with 6-7 branches; head 
hair 6 with 4-6 branches; siphon 
index about 7.0. 
{Aedimorphus) pampangensis 
Head hair 5 with 3-4 branches; head 
hair 6 with 2-4 branches (usually 
3); siphon index 3. 5-3.9 
.......... {Aedimorphus) alhoscutellatus 
7. Mouth brushes forming stout, serrate- 
tipped rods; ventral brush of more 
than 20 tufts 8 
Mouth brushes normal, usually with 
comb-like tips; ventral brush of no 
